The RV-5200 and RV-5300 Series operate as either a relief valve or low flow back pressure regulators. Adjustments are made through a non-rising stem available with an attractive knob, plain to allow insulation of OEM knobs, or flush for “back panel” applications. A typical application would be the use of a unit between a compressor and a load to prevent the compressor from “loading up” when dead-ended.